The present invention relates to an electric ratchet wrench and, more particularly, to an electric rapid ratchet wrench and a method of using the electric rapid ratchet wrench.
U.S. Pat. No. 8,800,410 discloses a ratchet wrench with a direction switching structure. The ratchet wrench includes a wrench body, a ratchet wheel, a ratcheting member, and a switching member. The ratchet wheel is rotatably mounted in the wrench body and can couple with a socket. The ratcheting member is mounted in the wrench body and is selectively engaged with the ratchet wheel by using a left half portion or a right half portion of ratchet teeth of the ratcheting member to switch the rotating direction of the ratchet wheel. The switching member is pivotably mounted in the body and abuts the ratcheting member.
A user has to grip the wrench body and repeatedly rotate the wrench body in opposite directions to drive the socket to thereby drive a fastener, such as a nut, coupled with the socket, which takes the user a long time doing so.
Electric wrenches have been provided to save the time for repeatedly rotating the wrench body in opposite directions. Electric wrenches generally include a power-driven motor, a driving member for coupling with a nut, and a transmission member between the motor and the driving member. An end of the transmission member is connected to and driven by the power-driven motor. The other end of the transmission member is connected to the driving member. Thus, the transmission member is driven by the motor to synchronously rotate the driving member to thereby drive the fastener coupled to the driving member.
Long bolts are commonly used on building construction sites which are usually located outdoors. The long bolts exposed outdoors are apt to rust, and the rusted area creates a resistance not permitting smooth passage of the nut. Thus, a user using a wrench has to apply a considerable force to overcome the resistance resulting from rusting to thereby make the nut pass through the large-resistance position in the rusted area. Therefore, use of conventional hand-driven wrenches is time-consuming and laborsome to the user.
If the torque of a motor of a conventional electric wrench is smaller than the resistance resulting from the rusting on a long bolt, the torque would be insufficient to drive the transmission member and the driving member to rotate, such that the nut cannot pass through the large-resistance position. At this time, an end of the transmission member is still rotated by the motor, and the other end of the transmission member cannot rotate the driving member due to the large resistance. Eventually, the transmission member is continuously distorted and, thus, deforms, and the driving member could disengage from the transmission member due to distortion of the transmission member. The motor could even burn.
In view of the foregoing, the conventional electric wrenches are useless when the torque provided by the motor is smaller than the force encountered by the electric wrenches. The interior structure of the electric wrenches is apt to damage, and the coils of the motor could burn and cause danger.
Thus, a need exists for a novel electric rapid ratchet wrench that mitigates and/or obviates the above disadvantages.